Abstract

We report insitu measurements of SiO(g) evolution during the oxidation of silicon by O2 for a range of experimental conditions including the transition from active to passive oxidation. The results show that this transition occurs when the SiO(g) partial pressure reaches the equilibrium vapor pressure for the reaction Si(s)+SiO(s)⇄2SiO(g). During the growth of a SiO2film, there is no significant transport of SiO molecules into the gas phase.